If you want to change the default loader text and background color then kindly follow the below step.
Open the file in this path /wp-content/themes/winery/header.php using some editor like DreamWeaver and scroll to line no: 29 approximately.
Here you can change the text as per your need.
Login to your WordPress backend and navigate to Admin Panel > Appearance > Customize > Additional CSS > Paste the below code.
You can change the color value as per your need.